cam_pos      = [-0.502691, 1.17901, -0.652324]';
cam_dir      = [-0.551142, 0.0315616, 0.833814]';
cam_up       = [0.187145, 0.978502, 0.0866624]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [1.08149, -0.271065, 0.725116]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;